Date: Mon, 11 Dec 1995 17:51:58 -0400
Sender: Vanagon Mailing List <vanagon@vanagon.com>
From: smitht@unb.ca (Tim Smith)
Subject: Re: DIY Head Gaskets, (Long) Please Check!
Vanagoonites or whatever we decided on. Would anyone who has done this job
please read and approve/correct this long message(sorry). Area I don't know
about are the cyl barrel gasket stuff, and general advice on the
sanity/mechanical worthiness of this CHEAPO approach to DIY gaskets, parts
are 2 gaskets, $30/ and a tube of goop, and likely some 13mm nuts etc. It
worked for my gushing '85, (gaskets/goop) and on the '87
(JBWeld/gaskets/goop) for 4+ and 1.5 years each. Thanks all, Tiny Tim.
DIY Head Gasket Procedure, Mk. I
----------------------------------------------------
OK, as memory serves me, done on an '85 1.9l engine.
Park it on a surface you can work on, can be dirt, just put a sheet of
something down to scrabble around on and catch the loose nuts.
Drain the coolant into a container, by opening the drain bolts between the
pushrod tubes on each side. need 6mm Allen head screw. Open the reservoir
cap to let in some air, watch for the flood, maybe 2-3gals. Open the front
radiator bleed screw, behind upper grill on passenger side to fully drain.
You may wish to consider a good rad rinse now, since the system is ready
for it. ie top up with fresh water, add rinse chemicals and run for 1/2
hour/til hot. then flush with clean water. Best place for a rinse kit
T-adapter is up front, under spare tire area, where there already is a
splice connector, just replace with T and flush, DO NOT LEAVE THE T IN PLACE!!!
Dispose of all liquids suitably.
CLEAN the engine thoroughly, GUNK it, wire brush/scrub it, hose it and wipe
it clean, NO LOOSE DIRT near the heads/block, NONE. I get paranoid opening
engines up, as you can see :>
Get comfortable underneath and remove the exhaust system. You can
disconnect at the CAT I _think_ and just take off front rear, and side
pipes. Breaking the nuts off with a nut-cracker is far more desirable than
stripping the studs in the engine block or bending/breaking a weakened pipe.
Pipes are $100++ each, take care! Seems like more effort, but pays
dividends in WD-40/heat/time/damage. F*ck one single stud and you are too!
Oversized studs/trips to dealer/Helicoil.... get the picture? A good
quality small nutcracker is worth its weight in gold, easy to use. Check
every exhaust support bracket, they are ALL esential and are dealer only
items unless you hit a junkyard find. Put them on the parts list as you go
if broken. They can be welded if just cracked through, welded! not brazed.
Take off the aircleaner and airflow control complete, loosen the band clamp
around the big air hose, pull off the other hoses, and unplug the wire
connector. Then unsnap the clips and remove. NOTE: when reinstalling DO NOT
PINCH any of the FI wires under the unit, against the metal supports as this
will meltdown your entire FI harness, $1150 at dealer!! (Hi Joel ;>)
Do passenger side first, pull off plug wires, and clean off the heads a bit
more as you likely missed some!!.
Undo FI injector system as a unit, no need to disconnect wiring or fuel
lines, OH, did you disconnet the battery before beginning :), if not do so now!
There are two bolts/injector, once off tug gently to get the units off the
head. You can remove the inlet tubes from the air distribution manifold,
black with 4 1.5" rubber/cloth tubes, this helps get things out of the way.
By now the head should be completely visible, and not connected to anything
except the block. If I forgot something, you figure it out. Draining the
engine oil is an option, as the pushrod tubes stay in place in the block.
If the van is badly tipped sideways/overfilled you may spill oil out the tubes.
Remove the valve cover, get a new gasket! Then start loosening the 8 big
nuts that hold on the head. Start loosening 1 turn or so each, working
around the head crisscross style the avoid warps. When all 8 bolts are
about 1/4" off the head try to push the head off by grabbing 2 pushrod tubes
and pushing off with your thumbs. Did you make sure this area of the head
was clean/clear too? No grit where the tubes insert into the head? Good.
Look from above now and grabbing the water jacket do the same trick of
pushing with your thumbs. What you want to do is pop off ONLY the head,
leaving the seals next to the case intact. One less area to wonder if dirt
got in. They head may need coaxing off, nylon hammer is best, small block
of wood and metal works OK, don't jiggle the water jacket! If you have to
pry, use a thin blade between the head and big gasket, and work around to
break the grip, gently does it, don't add to the problem. Once the head is
loose all around, then take the 8 nuts off.
When you have the heads off an inch or so, stick you fingers in and make
sure the cyl barrels aren't coming with it, didn't happen to me, but check!
Don't pull the heads off, push them with finger+thumbs in the gap. Less
likely to tug the entire side apart that way.
Holding the cylinder head in both hands high above your head, parade about
the yard while crying ecstatically. You will impress your neighbours with
your primitive man-machine thanks offering ritual, and they will not disturb
your contemplation from then on. Hurling the heads against the nearest wall
is simply too crude and brutish, and loses some of the mysticism.
Now have a good look at the head where the rubber gasket sat, get ready for
the $600 question, do I need new heads. Scrape it clean/clear with a
popsicle stick, use a stiff brush, nylon or wire, and put a shine back on
the seal area without putting in major scratches. Check the inner seal area
but don't use the wire brush here, seal is thinner and less compliant. If
the pits in the head are deeper than 1/8" I'd think about good used heads
or getting them weld filled by a REALLY GOOD WELDING SHOP, then machined
flat at the same place, could cost what good used heads would cost, check
prices carefully.
You can try filling pits with the JBWeld fill'n'smooth technique, you may
end up doing the heads again after a week if it doesn't take for you. It's
lasted 17 months for me so far. Again, the time spent in preparation is
well worth it, get the heads absolutely free of crud where you are going to
epoxy, spread it smooth and flat with NO air pockets, NONE. Take your time
squeegeeing in the epoxy to ensure the best possible bond. A surface nicely
roughened by sandblasting bonds well. Get it FLAT and SMOOTH, use a good
metal straight edge of some sort for the squeegee, and do a dry run to make
sure the edge will move all around the seat area without hanging up on a
tiny bump etc. in the casting. Let cure 24hrs.
While that's setting up clean up the rim of the water jacket of crud etc.
popsicle stick scrapper, fine sandpaper etc. Get it clean and shiny. Wipe
out any debris from inside the water jacket, be neat. Check out the
condition at the top of the barrels, should be OK. I re-used the inner
gaskets (or were there any there?). I said cheapo 'member?
When ready for reassembly, use Loctite/Permatex high temp silicone goop,
reddish brown colour, can't remember type. No Locktite? get the best you
can find, I don't use GE silicones, except for my bathtub. Ask around, if
they had JBWeld, they likely have Loctite stuff. Or buy the dealers goop $$$.
Apply the goop inside the new headgasket rim, NOT TOO THICK, just enough so
that it will seal the gasket to the water jacket, not ooze up then break off
and plug the coolant passages. install the gasket onto the water jacket and
get it properly seated all around, not trapped lips etc.
Then run a bead around the head where the gasket seats, again not too much.
If you had good heads/JBWeld/arc fixed a smear would do, mild pitting try
the squeegee method, plus a bead after the pits are packed. Don't count on
the head gasket to do this for you, DIY.
Slide the head onto the studs, OH, did I mention... get the studs
absolutely clean/dry before reassembly, and clean the base of the head nuts
and the area of the head they seat against, SPOTLESSLY. Then smear some
goop on the stud threads, and put a small bead on the base of each nut
before you spin it down to the head. Coolant will leak out around the nuts
if they are not properly gooped. Tighten crisscross, starting nearest to
centre and working out, VW rec. two torque levels, I usually take it slow,
few turns, then move on. Bring the nuts up to full torque eventually. DON'T
plan to retorque them when the goop dries as you will defeat the nice seal
you created. You want all this to happen while to goop is still soft.
Check the full torque stage 2-3 times, as the goop oozes very slowly and
will let off the clamping force. When the goop that oozed out onto the
water jackets (it will :) ) gets tacky/stiff, you better be done. Don't
forget that you have to fight with the push rods etc. It will pay you to
take off the rocker arms and do the pushrod stuff AFTER the heads are set-up
properly, less simultaneous fiddling. I can't remember, but I think I did it
this way.
and, my favorite line, re-installation is the opposite of these procedures.
Do the other side, the pain here being the water pump/belts/pulleys and
tight space to work in. Look for coolant weepage here carefully, maybe time
for a new pump while you are at it, sure saves labour.
Once both sides are done and dry, fill up the system completely, doing the
best you can without the engine running, then borrow a pressure tester and
pump it up to 15psi for a leak check. Let the pressure sit for a while, and
look carefully for head leaks, at gasket and nuts. If you find a leak,
repeat the ritualistic procession around the garden, but this time end by
hurling the heads to the pavement and jumping on them.
If they are dry, do the rest of the re-install, add new coolant, bleed
properly, then try it out. Remeber, there are likely many vans that drip in
a controlled/bearable manner. A few drops are not catastrophic, indeed,
you've likely bought several months time to sell your family and buy a new
engine from VW. Addictive little suckers, these wasserboxers :).
Good luck, Tim Smith
|